So, in the past when a supplement’s references were ‘broken’ (‘Codex: Eldar’ is now ‘Codex: Craftworld Eldar’), were allowances made?

The Relics aren’t suddenly overpowered, nor are the Warlord Traits. While being able to make a Gargantuan Creature both Character and Warlord is OP, Imperial Knights set that precedent a long time ago.

The only issue (but not, I think, a major issue) would be taking the Wraith Host formation and an Iyanden CAD. True the Spirit Seer from the CAD makes all Wraith Guard Troops, but the units from the formation do not have Objective Secured. Newer Codex v. Older Codex, the Wraith Guard from the formation would not ‘gain’ Objective Secured, even if they became (nominally) ‘Troops’. Yes?

I think a bunch of people got all verclempt over Eldar, with the power level of SM and the fact they get to keep their Suppliments, Iyanden should be good. Shit I only bought the thing a few years ago. If te ITC removed all Suppliments, I could go that way too.